A body is moving in a low circular orbit about a planet of mass \(M\) and radius \(R\). The radius of the orbit can be taken to be \(R\) itself. Then the ratio of the speed of this body in the orbit to the escape velocity from the planet is:
1. \(\sqrt{2}\)
2. \(\dfrac{1}{\sqrt{2}}\)
3. \(2\)
4. \(1\)

A spacecraft orbits a planet at an altitude of \(20~\text{km}\) above its surface. Assuming that the planet’s gravitational force is the only force acting on the spacecraft, how many complete revolutions does it make in \(24\) hours? Given that the mass and radius of the planet are \(8 \times 10^{22} ~\text{kg}\) and \(2 \times 10^6 ~\text{m}\) respectively, and the gravitational constant is \(6.67 \times 10^{-11} ~\text{Nm}^2 / \text{kg}^2.\)
1. \(13\)
2. \(9\)
3. \(17\)
4. \(11\)